Static pre-check · Sat, 15 Aug 2026 05:11:52 GMT
AI agents cannot complete MCP server initialization handshake and lack clear error response documentation for email delivery API calls.
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no link to an API reference in the homepage HTML
Fix: If you have an API, link its reference from the homepage. If you don't, this check is safe to ignore.
https://resend.com
5 docs link(s), e.g. https://resend.com/docs
Shows the current scan score and grade for this domain, straight from the latest static pre-check.
[](https://www.vorza.dev/score/resend.com)<a href="https://www.vorza.dev/score/resend.com"><img src="https://www.vorza.dev/api/badge/resend.com" alt="agent readiness score" /></a>106 characters
'Resend · Email for developers' (29 chars)
listed as (unnamed)
og:title and og:description present
all 6 agent crawlers may fetch /
HTTP 200, 143 bytes
robots.txt has a Sitemap: line
11 URL(s) listed
ratio 0.0336 — 14314 readable chars in 425552 bytes of HTML
Fix: Most of what you serve is markup and inline script rather than content. Reduce inline payloads or server-render more text so the signal-to-noise ratio favours readers.
1747 characters of text at /docs
HTTP 200 for / (agent UA)
https://resend.com/
1 valid block(s)
HTTP 200, 8036 bytes
HTTP 200, 5657 bytes
5 sampled link(s) all resolve
has headings and markdown links
Accept: text/markdown → text/markdown; charset=utf-8
both User-Agents got HTTP 200
14314 characters of text in the served HTML
0 redirect(s)
handshake failed: response was not a JSON-RPC message
Fix: Make https://resend.com/mcp answer a streamable-HTTP `initialize` request. Check that POST is allowed, that `Accept: application/json, text/event-stream` is honoured, and that the response is a JSON-RPC envelope.
no 4xx/5xx responses documented on any operation
Fix: Document your error responses with codes and schemas. Undocumented failures are where agent integrations silently break.
/agents.md not served (HTTP 404)
Fix: Publish /agents.md: what an agent may do here, which endpoints matter, auth requirements, and rate limits. It is the agent-facing counterpart to a README.
404 returns HTML, not a machine-readable body
Fix: Content-negotiate your errors: return a JSON body with a stable `code` (and a `next_action` where recovery exists) to clients that ask for JSON.
/docs → HTTP 200
1 scheme(s): bearerAuth
83/83 operations described (100%)
HTTP 200, 200008 bytes of JSON
OpenAPI 3.0.3, 47 path(s)
HTTP 200, valid JSON
/api → HTTP 404 (no API at the conventional root)
no listed MCP tools to inspect
no listed MCP tools to inspect
handshake did not complete, so tools/list was not reached
no agent-payment rail published — not applicable. This layer is excluded from the score rather than counted against the site.
no agent-payment rail published — not applicable. This layer is excluded from the score rather than counted against the site.
no agent-payment rail published — not applicable. This layer is excluded from the score rather than counted against the site.